Diagnostic Lab Testing for PVY, PMTV and TRV in Plant Tissue
There are times when diagnosis based on symptom expression needs to be confirmed with lab testing. There are currently three types of virus tests available to growers as follows.
ELISA (enzyme-linked immunosorbent assay): This is a very reliable serological test that uses virus-specific antibodies to detect the virus in either leaf or tuber tissue. ELISA does not differentiate strains of the virus and detection of virus from tubers is very inefficient. The test can be completed in 1-2 days.
Immunostrips: This is a serological test similar to ELISA but in an easy-to-use kit which can be used anywhere without the need for specialized equipment. The kits are currently not available for PMTV and TRV, but are available for PVY. This test can only be performed on leaf tissue. It is not as sensitive as ELISA and RT-PCR and does not differentiate strains of the virus. The kits can provide a result in the lab or field in less than 5 minutes.
PCR (polymerase chain reaction): This is a very reliable test used to detect a pathogen’s DNA or RNA in a sample. PCR is very specific and can be used to identify the strain of the virus, but currently only for PVY. The test can be completed in 1-2 days. Types of PCR testing used by the diagnostic labs listed below include RT-PCR (reverse transcriptase PCR), qPCR (quantitative PCR) and RT-ddPCR (droplet digital RT-PCR).
Please note that the diagnostic labs listed below are research labs, not commercial labs, and may have constraints regarding sample quantity and turnaround times. If you have many samples or an urgent request there are commercial labs, such as Agdia, that may be better able to meet your needs. Please contact them directly for more information.
Diagnostic Lab Testing for Powdery Scab in soil, potting mix and water
This tests looks for the presence and quantity of powdery scab resting spores (cytosori) in a sample (soil, potting mix, water) using qPCR (quantitative polymerase chain reaction). This test uses powdery scab-specific DNA sequences to detect resting spores. It is currently being offered at the Colorado State Plant Diagnostic Clinic (see contact information below).
Diagnostic Testing for PMTV in soil and potting mix
It is now possible to test for PMTV in both soil and potting mix. The test comprises reverse transcription real-time PCR (RT-qPCR) or/and droplet digital PCR (RT-ddPCR) assays of the total RNA extracted directly from the soil using a specific primer. This test is performed at the NDSU diagnostic lab (see contact information below).
Diagnostic Lab Testing for Stubby Root Nematodes in soil
This test looks for the presence and quantity of stubby root nematodes in a soil sample using qPCR (quantitative polymerase chain reaction). It is currently being offered by NDSU (see contact information below). Tests are currently being developed to detect TRV in stubby root nematodes.
Diagnostic Laboratories
Colorado State University
Plant Diagnostic Clinic
E215 Plant Sciences Building
1177 Campus Delivery
Colorado State University
Fort Collins, CO 80523-1177
Clinic Contact:
Ana Cristina Fulladolsa
Plant Diagnostic Clinic
Colorado State University
Website: http://plantclinic.agsci.colostate.edu/
Lab phone: (970) 491-6950
Email: plantlab@colostate.edu
Contact the lab for a list of services, fees and sample collection instructions.
Virus tests available: ELISA and RT-PCR for presence of PMTV and PVY. RT-PCR for TRV.
Powdery scab tests available: qPCR testing of soil, potting mix and water.
North Dakota State University
Neil C. Gudmestad (for virus testing from plant tissue, soil and potting mix)
Email: Neil.Gudmestad@ndsu.edu
Guiping Yan (for stubby root nematode testing)
Email: guiping.yan@ndsu.edu
Department of Plant Pathology/NDSU
306 Walster Hall
Fargo, ND 58105
Virus tests available: RT-PCR for presence of PMTV, TRV and PVY. PVY strain identification. PMTV detection from soil and potting mix using RT-qPCR or/and RT-ddPCR assays. Nominal fee based on the # of samples submitted.
Stubby root nematode test available: qPCR and quantification of stubby root nematodes in soil. Please follow the sampling instructions here Sampling Potato Fields for Stubby Root Nematodes.
Oregon State University
OSU Extension Plant Pathology Lab
HAREC
2121 South 1st Street
Hermiston, OR 97838
Phone: (541) 567-8321
Email: Hannah Rivedal rivedalh@oregonstate.edu or Ken Frost Kenneth.Frost@oregonstate.edu
Website: Hermiston Plant Pathology Diagnostic Laboratory Services
Virus tests available: RT-PCR for presence of PMTV, TRV and PVY. PVY strain identification.
Go to the website for information on sample submission.
University of Idaho
Alex Karasev
Plant, Soil and Entomological Sciences
University of Idaho
875 Perimeter Drive MS 2339
Moscow, ID 83844-2339
Phone: 208-885-2350
Email: akarasev@uidaho.edu
Virus tests available: ELISA and/or RT-PCR for PMTV, TRV and PVY. PVY strain identification available with RT-PCR.
USDA-ARS/Cornell University
Stewart Gray/Jason Ingram
Robert Holley Center for Agriculture
538 Tower Rd
Ithaca, NY 14853
Phone: 607-255-4596
Email: smg3@cornell.edu
Virus tests available: ELISA and/or RT-PCR for PMTV, TRV and PVY. PVY strain identification available with RT-PCR.
University of Wisconsin-Madison
Plant Disease Diagnostic Clinic
1630 Linden Dr. Room 183
Madison, Wisconsin 53706
Phone: 608-262-2863
Email: ppds@plantpath,wisc.edu
Website: Plant Disease Diagnostic Clinic
Virus tests available: Agdia immunostrips for PVY, the fee is $28/sample. RT-PCR for TRV, the fee is $55/sample. Go to the website for information on sample submission. If you are sending a sample from outside of WI please contact Brain Hudelson at 608-262-2863 or bdh@plantpath.wisc.edu.